Polymer concentration adjustment for homogeneous carbon nanofibers precursors

Abstract

Introduction. Carbon nanofibers CNFs have emerged as an important material in many advanced applications, especially those related to high electrical conductivity. Objectives. The primary objective of this study was to prepare a homogeneous CNFs’ precursor (Polyacrylonitrile PAN nanofibers) with improved graphitization through controlling one of the solution parameters, that is, polymer concentration. Methods. Precursors of PAN nanofibers with the addition of multi-walled carbon nanotubes MWCNTs were prepared with two concentrations of 8% and 10% w/v PAN/MWCNTs to adjust the insertion and uniform distribution of MWCNTs within the PAN nanofibers. Field emission scanning electron microscopy FESEM was used to evaluate the morphology of the electro spun nanofibers and uniformity of the MWCNTs distribution within the PAN nanofibers. Fourier transform infrared spectroscopy FTIR was also conducted to notice the interaction between MWCNTs and PAN to yield precursor with better graphitization characteristics. Results. FESEM results revealed more uniformity and homogeneity in the precursor structure with increasing PAN/MWCNTs concentration from 8% to 10% w/v. FTIR results showed increased intensity of the characteristic peaks of PAN and a new peak emerged at approximately 659 cm−1(C=C) which is potentially formed by interactions with MWCNTs and might be associated with cross-linking. Conclusion. Increased PAN/MWCNTs concentration from 8% to 10% w/v improved the insertion of MWCNTs inside PAN nanofibers and FTIR indicated the interactions between the added MWCNTs and PAN in the precursor with better graphitization characteristics.